You'll have to measure the bore to determine how much actual choke is there, just checking the muzzle "Only" tells what size the muzzle is. I don't know how much it takes but have heard say that Too Much Choke can give patterns worse than a good Cylinder bore.

The only way to truly know for certain is a pattern test.


Miller/TN
I Didn't Say Everything I Said, Yogi Berra